# d.py
#Place in \pythonXX\lib\site-packages\trac\wikimacros\


import re


# D keywords 
# from http://www.digitalmars.com/d/lex.html#keyword
# list checked 2005/03/18

keywords = ['abstract', 'alias', 'align', 'asm', 'assert', 'auto',
    'bit', 'body', 'break', 'byte',
    'case', 'cast', 'catch', 'cdouble', 'cent', 'cfloat', 'char', 'class', 'const', 'continue', 'creal', 
    'dchar', 'debug', 'default', 'delegate', 'delete', 'deprecated', 'do', 'double',
    'else', 'enum', 'export', 'extern',
    'false', 'final', 'finally', 'float', 'for', 'foreach', 'function', 
    'goto',  
    'idouble', 'if', 'ifloat', 'import', 'in', 'inout', 'int', 'interface', 'invariant', 'ireal', 'is',  
    'long',
    'mixin', 'module',
    'new', 'null',
    'out', 'override',
    'package', 'pragma', 'private', 'protected', 'public',
    'real', 'return',
    'short', 'static', 'struct', 'super', 'switch', 'synchronized',
    'template', 'this', 'throw', 'true', 'try', 'typedef', 'typeid', 'typeof',
    'ubyte', 'ucent', 'uint', 'ulong', 'union', 'unittest', 'ushort', 
    'version', 'void', 'volatile',
    'wchar', 'while', 'with']



# Regex Links

# http://www.amk.ca/python/howto/regex/regex.html#SECTION000310000000000000000
# http://docs.python.org/lib/matching-searching.html



def dIsAlpha(c):
#    /* true if c is a letter or an underscore, false otherwise */

    return c.isalpha() or (c == '_')


def dIsDigit(c):
#    /* true if c is a number or an underscore, false otherwise */

    return c.isdigit() or (c == '_')


def ishexdigit(c):
#    /* true if c is a hexadecimal digit, false otherwise */

    return re.compile("^[0-9A-F_]+$").match(c)


def isoctdigit(c):
#    /* true if c is an octal digit, false otherwise */

    return re.compile("^[0-7_]+$").match(c)


def issymbol(c):
    # /* true if c is legal D symbol, false otherwise */

    # /* "-" also needs to be escaped (in addition to the list at http://www.amk.ca/python/howto/regex/)? */
    return re.compile(r"^[?~:|!%{}\\\(\)\[\]\.,;=<>\+\-\*/&\^]+$").match(c)


def iskeyword(token): #, keywords):
#/* true if token is a D keyword, false otherwise */
    for x in keywords: #(i = 0; i < count(keywords.length; $i++)  /* keywords.length*/ 
        if (x == token):
            return True
    return False



class Stream: 

    # /* This somewhat emulates Phobos's Stream class, so I didn't have to completely rewrite d2html. */

    pos = 0
    src = ""
     
    def position(self):
        return self.pos
    
    def read(self):
        self.pos = self.pos + 1
        if(self.pos < len(self.src) + 1):
            return self.src[self.pos - 1 : self.pos]
        else:
            return " "

    def write(self, c):
        self.src = self.src + c

    def writeString(self, c):
        self.src = self.src + c

    def writeLine(self, c):
        self.src = self.src + c + "\n" # /* append with a newline */

    def __init__(self, s):
        self.src = s
        self.pos = 0



def execute(hdf, text, env):
    """
    This function is called when code is embedded in a trac wiki page:

    {{{
    #!d
    int main(char[] args)
    {
      printf("Hello World\n");
      return 0;
    }
    }}}

    The "d" indicates to use the D processor that this file contains.

    For more information, see http://projects.edgewall.com/trac/wiki/WikiProcessors.
    
    """

    # hdf is an HDFObjectType (and can't be concatenated with a string)
    # env is an instance (and can't be concatenated with a string)

    return d2html(text)



def d2html(raw_code):

    # * Copyright (c) 2001
    # * Pavel "EvilOne" Minayev
    # *
    # * Permission to use, copy, modify, distribute and sell this software
    # * and its documentation for any purpose is hereby granted without fee,
    # * provided that the above copyright notice appear in all copies and
    # * that both that copyright notice and this permission notice appear
    # * in supporting documentation.  Author makes no representations about
    # * the suitability of this software for any purpose. It is provided
    # * "as is" without express or implied warranty.
     
    # * Updated by J C Calvarese, http://jcc_7.tripod.com/d/, 2003/12/18
    # * Ported to Python by J C Calvarese, 2005/03


    # ### Porting Tips ###

    #    Concatenation:
    #    D:    ~
    #    PHP:  .
    #    Python: +


    # PHP do-while                   Python equivalent
    # ------------                   -----------------
    #                                doIt = True
    # do {                           while(doIt):
    #     ...                            ...
    #                                    if not(condition):
    # } while (condition)                    doIt = False

    # PHP for                        Python equivalent
    # -------                        -----------------
    # for (i = 0; i < spaces; i++)   for i in range(spaces):


    # By the way, string methods come in handy when doing text processing:
    # http://docs.python.org/lib/string-methods.html


    code = raw_code


    #/* Remove trailing CR and/or LF (doesn't seem to work, but doesn't seem to hurt either). */

    done = False

    while done == False:
        iLen = len(code)
        code = code.rstrip()
        if iLen == len(code):
            done = True

    tabsize = 4  #/* number of spaces in tab */
    lineNumber = 0
    spaces = 0

    
    #/* Colors for syntax highlighting, default values are
    #   Pavel Minayev's preferences in Microsoft Visual Studio editor   */

    Colors_keyword = "0000FF"
    Colors_number  = "008000"
    Colors_string  = "000080"
    Colors_comment = "808080"
    
    #useStyleSheet = True
    useStyleSheet = False

    xhtmlFormat = True 
    
    linestart = 0  #/* for tabs */
    c = ""
    c2 = ""
    
    src = Stream(code)
    dst = Stream("")

    c = src.read()
    while src.position() < len(code):
        if (c.isspace()):     #/* whitespace */

            doIt = True
            while(doIt): 
                if c == "\t": #/* tab character */
                    #/* expand tabs to spaces */
                    spaces = tabsize - (src.position() - linestart) % tabsize
                    for i in range(spaces):
                        dst.writeString(" ")
                    linestart = src.position() - tabsize + 1
                        
                elif c == "\n": #//10: /* linefeed */
                    linestart = src.position() + 1 #/* reset line start on newline */
                    dst.write(c)
                        
                elif c == "\r": #//13: /* control return */
                    linestart = src.position() + 1 #/* reset line start on newline */
                        
                    if(c2 != "\n"): #//10)
                            dst.write(c)
                        
                else: #/* space is left, anything else? */
                    dst.write(c)
                
                c2 = c
                c = src.read()
            
                if not c.isspace():
                    doIt = False

        elif (dIsAlpha(c)):    #/* keyword or identifier */
            token = ""
            doIt = True
            while(doIt):
                token = token + c
                c = src.read()
                if not(dIsAlpha(c) or dIsDigit(c)):
                    doIt = False
            
            if(iskeyword(token)):  #/* keyword */
                if(useStyleSheet):
                    dst.writeString('<span class="keyword">' + token + "</span>")
                else:
                    dst.writeString("<font color='#" + Colors_keyword +
                      "'>" + token + "</font>")
            else:  # /* simple identifier */
                dst.writeString(token)
                
        elif (c == '0'):  #/* binary, octal or hexadecimal number */
            if useStyleSheet:
                dst.writeString('<span class="number">')
            else:
                dst.writeString("<font color='#" + Colors_number + "'>")
            dst.write(c)
            c = src.read()
            if c == 'X' or c == 'x':   #/* hexadecimal */
                dst.write(c)
                c = src.read()
                while ishexdigit(c):
                    dst.write(c)
                    c = src.read()

                # /* TODO: add support for hexadecimal floats */
            elif (c == 'B' or c == 'b'):  #/* binary */
                dst.write(c)
                c = src.read()
                while c == '0' or c == '1' or c == '_':
                    dst.write(c)
                    c = src.read()
            else:    #/* octal */

                doIt = True
                while (doIt):
                    dst.write(c)
                    c = src.read()
                    if not(isoctdigit(c)):
                        doIt = False
                dst.write(c)
                c = src.read()

            if useStyleSheet:
                dst.writeString("</span>")
            else:
                dst.writeString("</font>")

        elif dIsDigit(c):    #/* decimal number */
            if(useStyleSheet):
                dst.writeString('<span class="number">')
            else:
                dst.writeString("<font color='#" + Colors_number + "'>")
            #/* integral part */
            doIt = True
            while(doIt):
                dst.write(c)
                c = src.read()
                if not(dIsDigit(c)):
                    doIt = False
            
            #/* fractional part */
            if c == '.':
                dst.write(c)
                c = src.read()
                while dIsDigit(c):
                    dst.write(c)
                    c = src.read()

            #/* scientific notation */
            if c == 'E' or c == 'e':
                dst.write(c)
                c = src.read()
                if c == '+' or c == '-':
                    dst.write(c)
                    c = src.read()
                while dIsDigit(c):
                    dst.write(c)
                    c = src.read()

            #/* suffixes */
            while c == 'U' or c == 'u' or c == 'L' or c == 'l' or c == 'F' or c == 'f':
                dst.write(c)
                c = src.read()

            if useStyleSheet:
                dst.writeString("</span>")
            else:
                dst.writeString("</font>")

        elif c == "\\":   #/* naked escape sequence (\) */
            if(useStyleSheet):
                dst.writeString("<span class=\"string\">")
            else:    
                dst.writeString("<font color='#" + Colors_string + "'>")
            dst.write(c)
            prev = c
            c = src.read()
            dst.write(c)
            c = src.read()
    
            if useStyleSheet:
                dst.writeString("</span>")
            else:
                dst.writeString("</font>")

        elif c == "\"":  #/* string (") with escape sequences  */

            if(useStyleSheet):
                dst.writeString('<span class="string">')
            else:    
                dst.writeString("<font color='#" + Colors_string + "'>")
            doIt = True
            while(doIt):
                if c == '<':   #/* special symbol in HTML */
                    dst.writeString("&lt;")
                else:
                    dst.write(c)
                
                prev = c
                if ((prev == '\\' and c == '"') or (prev == '\\' and c == '\\') and not isEscape): 
                    isEscape = True
                else:
                    isEscape = False
                
                c = src.read()
                if not(isEscape or c != '"'):
                    doIt = False
            
            dst.write(c)
            c = src.read()

            if useStyleSheet:            
                dst.writeString("</span>")
            else:
                dst.writeString("</font>")
            
        elif c == "'":   #/* character (') with escape sequences  */
            if useStyleSheet:
                dst.writeString('<span class="string">')
            else:
                dst.writeString("<font color='#" + Colors_string + "'>")
            doIt = True
            while(doIt):
                if c == '<':   #/* special symbol in HTML */
                    dst.writeString("&lt;")
                else:
                    dst.write(c)
                    
                prev = c
                
                if (prev == "\\" and c == "'") or (prev == "\\" and c == "\\") and not isEscape:
                    isEscape = True
                else:
                    isEscape = False
                
                c = src.read()
                if not(isEscape or c != '\''):
                    doIt = False
            
            dst.write(c)
            c = src.read()

            if useStyleSheet:            
                dst.writeString("</span>")
            else:
                dst.writeString("</font>")

        elif c == '`':  #/* character (`) with no escape sequences */
            if useStyleSheet:
                dst.writeString('<span class="string">')
            else:    
                dst.writeString("<font color='#" + Colors_string + "'>")
            doIt = True
            while(doIt):
                if (c == '<'):   #/* special symbol in HTML */
                    dst.writeString("&lt;")
                else:
                    dst.write(c)
                c = src.read()
                if c == "`": #/* 96 */
                    doIt = False
            dst.write(c)
            c = src.read()

            if useStyleSheet:
                dst.writeString("</span>")
            else:
                dst.writeString("</font>")

        elif issymbol(c):   #/* either operator or comment */

            if c == '<':   #/* special symbol in HTML */
                dst.writeString("&lt;")
                c = src.read()

            elif c == '/':  #/* could be a comment... */
                c = src.read()
                if c == '/':   #/* single-line one */
                    if useStyleSheet:
                        dst.writeString("<span class=\"comment\">/")
                    else:
                        dst.writeString("<font color='#" + Colors_comment + "'>/")
                    while c != "\n" and c != "\r": #//10 and $c != 13:

                        if c == '<':   #/* special symbol in HTML */
                            dst.writeString("&lt;")
                        elif c == "\t": #// 9
                            #/* expand tabs */
                            spaces = tabsize - (src.position() - linestart) % tabsize
                            for i in range(spaces):
                                dst.writeString(" ")
                            linestart = src.position() - tabsize + 1

                        else:
                            dst.write(c)
                        c2 = c
                        c = src.read()

                    if useStyleSheet:
                        dst.writeString("</span>")
                    else:
                        dst.writeString("</font>")

                elif (c == '*'):  #/* multi-line one */
                    prevprev = ""
                    prev = '/'
                                        
                    if useStyleSheet:
                        dst.writeString('<span class="comment">/');
                    else:                        
                        dst.writeString("<font color='#" + Colors_comment + "'>/")
                    doIt = True
                    while(doIt):
                        if c == '<':   #/* special symbol in HTML */
                            dst.writeString("&lt;")
                        elif (c == "\t"): #//9)
                            #/* expand tabs */
                            spaces = tabsize - (src.position() - linestart) % tabsize
                            for i in range(spaces):
                                dst.writeString(" ")
                            linestart = src.position() - tabsize + 1
                        else:
                            if(c == "\n" or c == "\r"): #//c == 10 || c == 13)
                                linestart = src.position() + 1 #/* reset line start on newline */                            
                            dst.write(c)
                        prevprev = prev
                        prev = c
                        c = src.read()
                        if prevprev != '/' and prev == '*' and c == '/':
                            doIt = False
                    dst.write(c)

                    if useStyleSheet:                    
                        dst.writeString("</span>")
                    else:
                        dst.writeString("</font>")
                    
                    c = src.read()

                elif (c == '+'):  #/* nestable multi-line comment */

                    prevprev = '/'
                    prev = '+'
                    level = 0                    
                    
                    if useStyleSheet:
                        dst.writeString("<span class=\"comment\">/")
                    else:
                        dst.writeString("<font color='#" + Colors_comment + "'>/")
                    doIt = True
                    while(doIt):
                        if (c == '<'):   #/* special symbol in HTML */
                            dst.writeString("&lt;")
                        elif (c == "\t"): #//9)

                            #/* expand tabs */
                            spaces = tabsize - (src.position() - linestart) % tabsize
                            for i in range(spaces):
                                dst.writeString(" ")
                            linestart = src.position() - tabsize + 1

                        else:
                            #/* reset line start on newline */
                            if (c == "\n" or c == "\r"): #//10 || $c == 13)
                                linestart = src.position() + 1
                            dst.write(c)
                            
                            if (prev == '/' and c == '+'):
                                level = level + 1
                            
                            if (prevprev != '/' and prev == '+' and c == '/'):
                                level = level - 1
                        prevprev = prev
                        prev = c
                        c = src.read()
                        if prev == '+' and c == '/' and level == 0:
                            doIt = False
                    dst.write(c)
                    if useStyleSheet:
                        dst.writeString("</span>")
                    else:
                        dst.writeString("</font>")
                    c = src.read()
                else:    #/* just an operator */
                    dst.write('/')

            else:    #/* just an operator */
                dst.write(c)
                c = src.read()
        else:
            #/* whatever it is, it doesn't seem to be valid */
            dst.write("{error!}")

    dst.write(c)
    strippedSrc = dst.src.strip
    if(strippedSrc != ""): #/* make sure there's actual content */
        return "<pre class=\"code-block\"><code>" + dst.src + "</code></pre>"
        #  class=\"example\"
    return ""